Your Green Life: "Torrefaction Fuel"

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KBJR News 1

October 11, 2012Updated Oct 11, 2012 at 7:54 AM CST

Duluth, MNThe Natural Resources Research Institute has a number of projects that they're working on to develop new products and methods that are sustainable. The goal is to develop a new process that will reduce, or eliminate, the need for coal.

"The process is called torrefaction, and torrefaction is basically, think of roasting, you're roasting it in an environment of low oxygen and what that does is that allows you to drive off the natural volatiles in the biomass, or wood in our case. And it results in a more dense substrate." said Tim Hagen, a Chemical Engineer for NRRI.

The end product is basically a roasted wood chip with more energy available to burn than a non–roasted woodchip.Once the roasting is complete the chips are ground up.

Hagen says, "So then when you get that powder it is easily densifiable into pellets, or briquettes, or even bricks, or even torrefaction pellets. You can take this material and pelletize it."

There are no pollutants, such as sulfates and mercury, that are found in coal, and it's renewable, transportable, and stores well for long periods of time.

"Another advantage of densified torrefaction is that it becomes hydrophobic, so that it repels water. You can see these torrefaction pellets have been under water for a series of months here and they are still pellets." Hagen said.

The NRRI hopes that this will one day be a more environmentally friendly substitute for coal.At some point they hope to start the first biomass fueled passenger train.